The objectives of this proposal are to establish the structural bases for the biological activities of heparins and heparan sulfates. Crude heparin and heparan sulfate preparations will be fractionated according to charge and molecular weight and the separated fractions will be assayed for anticoagulant activity and for their content of D-glucuronic and L-iduronic acids, N-sulfated and N-acetylated D-glucosamine, and each type of sulfated monosaccharide. A variety of new procedures will be used to characterize the structures of different fractions, including nearest neighbor analysis and chromatographic profiling of amounts and kinds of oligosaccharides released when fractions are subjected to selective cleavage reactions under carefully controlled reaction conditions. Quantitation of mono- and oligo-saccharides obtained in these studies will be based upon the amount of 3H recovered in each component after it is carboxyl-reduced or aldehyde-reduced with sodium (3H) borohydride.